Electronic gas cleaner having an improved electrical connection



March 1, 1966 A. GILBERTSON 3,237,383 ELECTRONIC GAS CLEANER HAVING ANIMPROVED ELECTRICAL CONNECTION Filed Sept. 20, 1963 INVENTOR. L /v/v/Z67435230 ATTOPA/EV WLLUHHWHULLMWMMM I l 33 Y/TI United States Patent3,237,383 ELECTRONIC GAS CLEANER HAVING AN IM- PROVED ELECTRICALCONNECTION Lynn A. Gilbertson, Minneapolis, Minn., assignor to HoneywellInc., a corporation of Delaware Filed Sept. 20, 1963, Ser. No. 310,245 4Claims. (Cl. 55139) The present invention is concerned with an improvedgas cleaning apparatus and more particularly with an electronic gascleaner of the type having one or more cleaning cells slidable into andout of a frame which is mounted in an air flow duct. Specifically thisapplication is concerned with an electronic gas cleaner of the typedescribed above and having a high voltage power supply mounted in theframe and a unique flexible electrical connection arrangement forconnecting the output of the high voltage power supply to the individualcells.

It is well known in the electronic gas cleaner art to provide a framestructure which is mounted in a gas flow duct generally transverse tothe direction of gas flow. It is also known to have this frame providedwith an opening through Which an electronic gas cleaner cell can be slidinto and out of the frame. In many installations this is necessarybecause the cell must occasion-ally be removed for cleaning. Also, inmany installations removal of the cell is the only manner in whichrepairs can be made to the unit. In such installations the high voltagepower supply for the electronic cell is generally located in the frameand hence is not removable with the cell.

In all such installations, one of the problems which has been faced isthe manner of electrically connecting the high voltage power supply tothe electronic gas cleaner cell. The connection must be one which allowsremoval of the cell easily and quickly and, on the other hand, theelectrical connection must be such that when the cell is in place goodelectrical contact is maintained. In the past, numerous arrangementshave been proposed for accomplishing such an electrical connection. Forexample, button type connectors have been provided which are a-butted bythe cell when it is slid into place or when a door is closed. This typeof connector generally operates satisfactorily except that themanufacturing tolerances in building the unit must be such that the cellalways engages the buttons or no electrical connection, or at least nota satisfactory connection, is obtained. Another approach is in the useof leaf type connectors of spring steel or other conductive materialwhich are engaged by a contact as the cell is moved into the frame. Oneof the major problems in this type of connector is that, while the cellcan he slid into the frame easily and a good contact is obtained,difliculty is often encountered in removing the cell from the frame.Various other types of connectors which have been used in the past havepresented similar problems.

The present invention provides, in combination with an electronic gascleaner of the type described above, an improved electrical connectionbetween the high voltage power supply and an electronic gas cleanercell. This electrical connector structure facilitates easy insertion andwithdrawal of the gas cleaner cell into the frame and also insures goodelectrical connection even over relatively wide manufacturing tolerancesin the relative sizes of the gas cleaner cell and the frame.

The present invention provides a plurality of contact surface on oneedge of the gas cleaner cell which extends in a direction along whichthe cell is moved in sliding it into or out of the frame. The frame hasmounted therein an insulative member which is positioned generallyparallel to the edge of the cell having the contact surfaces thereon.This insulative member is mounted for move- 3,237,383 Patented Mar. 1,1966 ment toward and away from the cell and is normally biased towardthe cell. Mounted on this insulative member is a plurality of connectormembers, one adapted to engage each of the contact surfaces. Theseconnector members are of an oblong shape and are pivotally mounted onthe insulative member. Each of the contact members is yieldably biasedso that one end of it extends toward the cell. In adidtion each of theseconnector members is connected to one of the output terminals of thehigh voltage power supply. The insulative member is positioned in theframe so that, as the gas cleaner cell is slid thereinto, the contactsurfaces engage the connector members and pivot them in opposition tothe means which normally bias them in a direction toward the cell. Thusgood electrical contact is established between the con nector membersand the corresponding contact surfaces. Also by making the connectormembers relatively long, the relative sizes of the frame and the gascleaner cell can vary rather significantly and electrical contact isstill established. Each of the contact surfaces is electricallyconnected to one of the sets of electrodes in the gas cleaner cell.

This unique electrical connection may find application in units whereina single cell is slid into the frame and it may also find application inlarger installations wherein two or more cells are slid into anelongated frame, one after another. Due to the fact that the insulatedmember is mounted for movement toward and away from the cell, the cellcan be easily removed. As the cell is slid from the frame, the connectormembers are pivoted and as this occurs the insulative member on whichthey are mounted is moved away from the cell in opposition to the meanswhich normally biases it toward the cell. Thus the cell can be removedwithout any binding between the con tact surfaces and the connectormembers.

Thus it is seen that the unique connector arrangement which is thesubject of the present invention overcomes the objections which havebeen found with regard to the previously used connectors in electronicgas cleaners of the type described.

Therefore an object of the present invention is to provide, incombination with an electronic gas cleaner of the type having a fixedframe structure and a gas cleaner cell slidable into and out of theframe, an improved electrical connection between the high voltage powersupply and the gas cleaner cell.

Another object of the present invention is to provide, in combinationwith an electronic gas cleaner of the type having a fixed framestructure and a high voltage power supply mounted therein and anelectronic gas cleaner cell slidable into and out of the frame, animproved electrical connector structure for connecting the output of thehigh voltage power supply to the gas cleaner cell, this connectorstructure providing good electrical contact While rendering the celleasily slidable into and out of the frame.

Another object of the present invention is to provide, in combinationwith an electronic gas cleaner of the type described above, anelectrical connection between the high voltage power supply and the gascleaner cell which provides good electrical connection even whenrelatively large manufacturing tolerances exist in the size of the frameand of the gas cleaner cell.

Further objects and advantages of my invention will become apparent tothose skilled in the art upon reading the following detailed descriptionof a preferred embodiment of the invention in conjunction with theaccompanying drawing wherein:

FIGURE 1 is an elevational view with portions broken away of anelectronic gas cleaner having incorporated therein the presentinvention.

FIGURE 2 is an end view, partially in cross section, taken along line 22of FIGURE 1.

FIGURE 3 is a fragmentary perspective view showing in detail theelectrical connector structure of the present invention.

FIGURE 4 is a fragmentary elevational view, partially in cross section,of the electrical connector structure of the present invention.

Referring first to FIGURES 1 and 2, numeral 1th gener-ally designates anelectronic gas cleaning apparatus of the type which is adapted to beused in connection with forced air heating and cooling systems. Theapparatus includes a frame structure 11 which is adapted to be mountedin an air flow duct (not shown) in a direction generally transverse tothe direction of air flow. The frame may be constructed of any metal orany other material and may be of a welded or otherwise assembledconstruction. Frame 11 includes an air inlet opening 12 and an airoutlet opening 13 as best seen in FIGURE 2. Frame 11 also includes,adjacent the bottom thereof, a horizontally extending shelf-like member14 and toward the top thereof a further horizontally extendingshelf-like member 15. Members 14 and 15 may be mounted in the frame bywelding or any other appropriate means (not shown). At the right handend of the frame, as seen in FIGURE 1, is provided an access door 16which is preferably hinged near the bottom of the unit and which, whenclosed, covers an access opening in the frame.

Mounted on the upper side of shelf member 14 is a pair of guide members'17 and 17 which are arranged in spaced parallel relationship andextending substantially the entire width of the frame. In between thesetwo guide members is a raised rounded portion 20 which also extendssubstantially the entire width of the frame.

Mounted on the under side of shelf 15 is a corresponding pair of guidemembers 21 and 21. Members 17 and 17 and 211 and 21' act as guides foran electrostatic gas cleaner cell 22 which is slid into and out of frame11 through the access opening which is normally covered by door 16. Whenthe cell is slid into the frame, the raised rounded portion 20 providesa bottom sliding surface to prevent galling of the underside of thecell.

Cell 22 may be of any conventional construction but preferably is of thetwo stage type having an ionizing and a collecting section and may, forexample, be of the type shown in the Keith M. Nodolf Patent Number3,028,715 which issued April 10, 1962. As is well known in the art, thistype of cell includes a set of high voltage electrodes and a set ofgrounded electrodes in the ionizing section and also a connector sectionwhich includes a set of high voltage electrodes and a set of groundedelectrodes which are alternately interleaved. It is customary,particularly in smaller units of the type used for residentialapplications, to use a single power supply for the ionizing andcollecting sections. However in order to prevent arcing between therelatively closely spaced alternately charged plates of the collectorsection, a relatively high ohmic value resistor is provided between thepower supply and the high voltage plates of the collector section.

The power supply in the present unit has been shown rather schematicallyas element 23 mounted on the upper side of the shelf member 15. Thedetails of this power supply have not been shown since any of a numberof power supplies may be used and normally would include a high voltagetransformer and a voltage doubling circuit for transforming relativelylow voltage A.C. current to relatively high voltage DC. current. Thisalternating current voltage may be supplied to power supply 23 from anyconventional source (not shown) from which an electrical cable mayextend to a terminal box 24 mounted on the upper exterior of the frame11. From terminal box 24 the current may be supplied to the power suppiythrough a pair of conductors 25 and 26 as shown in FIGURE 1.

Also mounted on shelf members 14 and 15 respectively Cit are a pair ofU-shaped guide members 27 and 30. Slidably mounted in these U-shapedguide members is a mechanical prefilter 31 which may be of anyconventional type and, for example, may be simply a screen for removinglarge particles from the air before it reaches the electronic cell.

Numeral 32 generally designates an improved electrical connectorstructure for connecting the output of the high voltage power supply 23to the electrodes of the electronic air cleaner cell 22. This connectorstructure can best be seen in FIGURES 3 and 4. FIGURE 3 is a fragmentaryperspective view showing in detail the connector structure 32 in aposition occupied by certain components thereof as the cell 22 is beingslid into the frame 11. FIGURE 4 is also a fragmentary view anddiscloses the connector structure when the cell is in its normaloperating position within the frame 11.

As seen in FIGURES 3 and 4, the connector structure 32 includes aninsulative member 33 which is made up of an insulative board 34 which ismounted directly above and parallel to shelf member 15 and a secondinsulative board 35 extending substantially perpendicular to board 34.Board 35 may be mounted on board 34 by appro priate means such asL-shapcd members 36 and rivets 37. Insulative member 33 is movablymounted on shelf 15 by a pair of upstanding pin members 40 and 41 whichare rigidly mounted on shelf 15 and which extend loosely throughapertures 42 and 43 in board 34. Pins 40 and 41 have, at their upperends, enlarged head ortions 40 and 41 respectively. Mounted on the pins40 and 41, intermediate the board 34 and their head portions 40 and 41',are spiral springs 44 and 45 respectively. These springs normally urgeboard 34 into engagement with shelf 15 and hence toward the air cleanercell but allow movement of the insulative member away from the cell inopposition to the force of the springs.

Mounted on the upper edge of the cell 22 are three flat electricallyconductive surfaces 46, 47, and 50. These surfaces are electricallyconnected to the electrodes of the gas cleaner cell. For example,surface 46 may be connected to the high voltage electrodes of the aircleaner ionizing section. Surface 47 may be connected to the highvoltage electrodes of the collector section. Surface 50 may be connectedto the grounded electrodes of both the ionizing and collecting section.As pointed out previously herein, it is customary to provide arelatively large resistance between the power supply and the highvoltage electrodes of the collector section to prevent arcing and henceit is necessary to have separate connections for the high voltageelectrodes of the ionizer and collector sections. The manner in whichconductive surfaces 46, 47, and 50 are connected to the electrodes ofthe air cleaner cell is not shown in the drawing but it is to beunderstood that this connection may be made in any conventional manner.

Mounted on the vertically extending board 35 of the insulated member 33are three elongated electrically conductive collector members 51, 52,and 53 which co-act with contact surfaces 46, 47, and 50 to provide anelectrical connection therewith. Each of the connector members 51, 52,and 53 is pivotally mounted on the board 35 by appropriate means such aspins 54. As seen in FIGURES 3 and 4, these connector members areelongated and have rounded ends and are pivoted at or near theircenters. The lower end of connectors 51 and 52 extend through arectangular opening 55 in board 35 and a similar but somewhat largeropening 56 in shelf member 15. Similarly the lower end of connector 54extends through a rectangular opening 57 in board 34 and through theopening 56 in shelf member 15. Connector members, 51, 52, and 53 arespring biased to a position whereintheir lower ends extend toward theair cleaner cell by electrically conductive spring members 58, 60, and611 respectively. These spring members are connected to. electricallyconductive fastener members 6Z, nd.

These fastener members are in turn mounted on board 35 by appropriatemeans such as pins or rivets 65 which mechanically connect them to theboard 35 and electrically connect them to electrical conductors 66, 67,and 70 respectively. These electrical conductors may in turn beconducted to the output terminals of the high voltage power supply 23.As pointed out previously herein, a high ohmic value resistor ispreferably inserted between the high voltage power supply and theconductor 67.

Due to the action of the springs 58, 60, and 61, the electricalconnectors 51, 52, and 53 generally extend in a direction so that theirlower ends extend into the opening in the frame which is to be occupiedby the air cleaner cell. As the cell is slid into the frame, the contactsurfaces 46, 47, and 50 engage the lower ends of these connectors, andas the cell is slid into the frame, these connectors are pivoted inopposition to the force of their springs. Obviously the amount that theconnectors are pivoted depends upon the distance which they extend intothe space which is to be occupied by the cell and also the spacingbetween the top edge of the cell and the shelf 15. When the cell is slidinto place the connector members are held firmly in contact with thecontact surfaces by their spring members.

If the connector members are made relatively long, it can be seen that arelatively large variation in dimensions of the frame and the aircleaner cell may exist without effecting the electrical connectionbetween the connector members and the contact surfaces. This is a greataid in manufacturing the units since it is common knowledge thatmanufacturing costs depend a great deal upon the strictness of themanufacturing tolerances which must be met.

When the cell is to be removed from the frame the connector memberspivot in the opposite direction as the cell is removed. This is possiblesince the insulated member 33 is moved upward in opposition to thesprings 44 and 45 which urge the insulated member toward the cell.

As pointed out previously herein, this unique connector structure findsapplication not only in structures as disclosed herein wherein a singlecell is removably mounted in the stationary frame, but is particularlyadvantageous in applications where a plurality of cells are slid into aframe.

From the foregoing it can be seen that I have provided, in combinationwith an electronic gas cleaner of the type having a cell which isslidable into and out of a stationary frame and wherein the high voltagepower supply is mounted in the frame, a unique electrical connectorstructure which assures good electrical connection and yet renders thecell easily slidable into and out of the frame. In addition thestructure insures good electrical contact even when there are relativelylarge variations in the dimensions of the cell and the frame.

Various modifications to the structure described herein can obviously bemade by those skilled in the art without departing from the presentinvention. Therefore the invention is not intended to be limited to thepreferred embodiment described herein but it is intended that it shallbe limited solely by the scope of the appended claims.

I claim as my invention:

1. In an electronic gas cleaner including a frame adapted to be mountedin a gas flow duct, a gas cleaner cell slidable into and out of saidframe through an access opening at one side of said frame, and a highvoltage power supply for said cell, said power supply being mounted insaid frame and spaced from said cell, means for electrically connectingsaid cell to said power supply comprising: a generally flat electricalcontact surface on one edge of the cell; a cooperating elongatedelectrically conductive connector member adapted to be electricallyconnected to an output terminal of the power supply; an insulativemember; means movably mounting said insulative member in said frame in agenerally spaced parallel relationship with the edge of the cell havingsaid contact surface thereon, said means rendering said insulativemember movable toward and away from said one edge; means yieldablyurging said insulative member toward said cell; means pivotally mountingsaid connector member on said insulative member; and means yieldablybiasing said connector member to an angular position wherein one endthereof extends toward the cell, said insulative member being positionedin said frame so that said contact surface on the cell slidably engagesand causes pivotal movement of said connector member when the cell isslid in the frame and thereby insures good electrical contact betweensaid connector member and said contact surface.

2. In an electronic gas cleaner including a frame adapted to be mountedin a gas flow duct generally transversely to the direction of gas flowand having an access opening at one side thereof, a gas cleaner cellslidable into and out of said frame through the access opening, saidcell having a generally flat electrical contact surface on an edgethereof which extends in the direction in which the cell is slid intoand out of the frame, and a high voltage power supply for said cell andmounted in the frame in spaced relationship with the cell, means forelectrically connecting said high voltage power supply to said cellthrough said electrical contact surface thereon comprising: aninsulative board; means resiliently mounting said board in said frame ina generally spaced parallel relationship with the edge of said cellhaving the flat contact surface thereon, said means including meansmounting said board for movement toward and away from said cell andmeans normally urging said board toward said cell; an elongatedelectrically conductive connector member; means pivotally mounting saidconnector member on said insulative board for angular movement withrespect thereto in a plane generally in alignment with said flat contactsurface, the position of said insulative board in said frame being suchthat said elongated connector member engages said contact surface incertain angular positions and such that said connector member clearssaid contact surfaces when said member is pivoted to certain otherangular positions; yieldable means normally biasing said connectormember to an angular position wherein it engages said contact surface toprovide an electrical connection therewith; and means electricallyconnecting said connector member to an output terminal of the powersupply.

3. In an electronic gas cleaner: a frame adapted to be mounted in a gasflow duct generally transversely to the direction of gas flow; an accessopening at one side of said frame; a gas cleaner cell slidable into andout of said frame through said access opening; a power supply for saidgas cleaner cell, said power supply being mounted in said frame andbeing adapted to be connected to a source of current, said power supplyincluding output terminals; an electrical contact surface on one edge ofsaid cell which extends in the direction in which said cell is slidableinto and out of said cell; an insulative member; means mounting saidinsulative member in said frame in generally spaced parallelrelationship with said one edge of said cell for movement toward andaway from said cell; means yieldably biasing said member toward saidcell; an elongated electrically conductive connector member cooperablewith said contact surface; means pivotally mounting said connectormember on said insulative member for angular movement with respectthereto in a plane generally in alignment with said contact surface; aconductive spring member physically and electrically connected to saidconnector member and biasing said connector member to a position whereinone end thereof extends toward said cell, said insulative member beingpositioned in said frame so that said contact surface on said cellslidably engages and causes pivotal movement of said connector member inopposition to said spring member when said cell is slid into said frameand thereby insures good electrical contact between said connectormember and said contact surface; and means electrically terminal of saidpower supply.

4. In anelectronic gas cleaner of thettype having a.

frame, a gas cleaning cell slidable into and. out 'of the frame, and apower supply mounted in the frame to supply power to the cell, aflexible electrical connection between the power supply and the cellcomprising: an electrical contact surface on one edge of the.cell, whichedge extends in the direction in which the cell is slid into and out ofthe frame; an insulative member mounted in said frame for movementtoward and away from said one edge of the cell; means resiliently urgingsaid insulative member toward said one edge, of the cell; an electricalconnector member; mounting means pivotally mounting said connectormember on said insulative member for rotation about an axis transverseto the direction in which the cell is slid into and out of the frame sothat a portion of said connector member is angularly movable into andout of engagement with said'contact surface when the ,cell is disposedin the frame; yieldable means urging said connector member to anangularposition wherein said portion thereof engages said contact A surface;-and means electrically connecting saidconnector member to an outputterminal of the'power' supply.

References Cited by the Examinerv UNITED .STATES PATENTS ROBERT F;BURNETT, Primary Examiner.

Berly et a1; 55-145

4. IN AN ELECTRONIC GAS CLEANER OF THE TYPE HAVING A FRAME, A GASCLEANING CELL SLIDABLE INTO AND OUT OF THE FRAME, AND A POWER SUPPLYMOUNTED IN THE FRAME TO SUPPLY POWER TO THE CELL, A FLEXIBLE ELECTRICALCONNECTION BETWEEN THE POWER SUPPLY AND THE CELL COMPRISING: ANELECTRICAL CONTACT SURFACE ON ONE EDGE OF THE CELL, WHICH EDGE EXTENDSIN THE DIRECTION IN WHICH THE CELL IS SLID INTO AND OUT OF THE FRAME; ANINSULATIVE MEMBER MOUNTED IN SAID FRAME FOR MOVEMENT TOWARD AND AWAYFROM SAID ONE EDGE OF THE CELL; MEANS RESILIENTLY URGING SAID INSULATIVEMEMBER TOWARD SAID ONE EDGE OF THE CELL; AN ELECTRICAL CONNECTOR MEMBER;MOUNTING MEANS PIVOTALLY MOUNTING SAID CONNECTOR MEMBER ON SAIDINSULATIVE MEMBER FOR ROTATION ABOUT AN AXIS TRANSVERSE TO THE DIRECTIONIN WHICH THE CELL IS SLID INTO AND OUT OF THE FRAME SO THAT A PORTION OFSAID CONNECTOR MEMBER IS ANGULARLY MOVABLE INTO AND OUT OF ENGAGEMENTWITH SAID CONTACT SURFACE WHEN THE CELL IS DISPOSED IN THE FRAME;YIELDABLE MEANS URGING SAID CONNECTOR MEMBER TO AN ANGULAR POSITIONWHEREIN SAID PORTION THEREOF ENGAGES SAID CONTACT SURFACE; AND MEANSELECTRICALLY CONNECTING SAID CONNECTOR MEMBER TO AN OUTPUT TERMINAL OFTHE POWER SUPPLY.